This application proposes the establishment of a Program Project at Baylor College of Medicine to study male infertility with a focus on investigation the etiology of abnormal sperm production and the application of assisted reproductive techniques to overcome these defects. The Program Project will have as its nucleus a core administrative unit that will coordinate the activities of the basic and clinical scientists on a day to day basis. The focus of this Program Project will be in the area of the molecular biology of male infertility with specific emphasis on defining the genes required for normal spermatogenesis. Assisted reproductive techniques have been used to overcome many male factor defects. It is assumed that if a sperm can fertilize, than it is "healthy". We have no scientific basis for this belief and many of these offspring could be carrying genetic defects. The aims for the proposal are: 1. To establish a program project for the study of male infertility creating a close working relationship between basic and clinical scientists from the Departments of Urology, Obstetrics and Gynecology., Cell Biology, and Medical Genetics. Bring these groups together in one project will create a more effective focus on male infertility than would occur with these scientists working individually. 2. To Create a facility to analyze DNA and perform in situ hybridization represents a significant a significant and critical component of this Program Project. 3. To correlate clinical features of male infertility with new discoveries at the mo level, to better understand the diseases processes and thereby to develop ad more effective treatment and diagnostic modalities. The expertise of this multi-disciplinary group of scientists working together is expected to yield new understanding of the basic pathophysiology of male infertility.